More detailed testing needs to be done tracking the transitions for AsyncChannel

[phausler]

The changes associated with 047ab6a need to have some sort of test that triggers that previous behavior to prove that the change listed definitely does what we think it does (which I am pretty sure it is correct). Having tests to prove its correctness will aide in preventing possible regressions etc.

[twittemb]

Just for the record: both AsyncChannel and AsyncThrowingChannel should have those tests.

[FranzBusch]

We can close this issue since we have re-implemted the AsyncChannel and added tests.